**Role:** React Frontend engineer (Medior/Senior) **Location:** Lisbon (Hybrid) **Start Date:** January 2026 **Salary:** Competitive with benefits **Why Are We Hiring?** As we continue to scale our expense management platform, we are looking for a talented Software Engineer to join our fast\-paced and international engineering team. You will play a key role in modernizing one of our main products, through AI. This role is ideal for someone with a strong technical foundation who thrives in a collaborative and agile environment and loves to explore AI technology. **What Will You Do:** * Designing, developing, and maintaining front end React applications, connecting to a .NET 8\.0 backend, as part of an agile development team. * Design scalable systems and write robust, maintainable code following best practices for software development. * Contribute to architectural decisions and codebase improvements. * Heavily rely on AI to quickly iterate and develop frontend solutions. * Ensure quality via unit testing, code reviews, and continuous integration. * Work closely with product managers and designers to bring product vision to life. * Participate in regular sprints and collaborate cross\-functionally with Backend Engineers, QA, DevOps, Support and Product teams. **About You:** Bachelor’s degree in Computer Science, Engineering, or equivalent experience. 2\-3 years of experience in frontend React development. A team player with strong problem\-solving skills and attention to detail. ️ **Tools Proficiency:** * Solid experience developing React based frontends. * Experience with companywide design systems, both in using them in your everyday development and also contributing to their development. * Experience in interacting with RESTful APIs * Attention to testing, namely experience using Jest for unit test. * Experience with React design patterns, State management, consuming RESTful APIs **Nice to havee:** * Experience in the fintech industry (or similar) is a plus. * Familiar with Git, CI/CD pipelines * **Knowledge of .NET 8\.0** (this is a frontend position, but you’ll be interacting with a .NET 8 backend) **Analytical skills and AI proficiency:** all team members are expected to demonstrate strong analytical capabilities and make smart use of AI tools, whatever helps them work smarter and drive results in their role. **Language Skills:** fluent English, any other language is a plus **Why Join Mobilexpense?** We’re not a giant enterprise. We’re a growing B2B SaaS scale\-up with 3,000\+ customers and big ambitions. Here, you’ll be empowered to build, test, and own your growth engine—without red tape or layers of approvals. * Work with a **diverse, international team** (27 nationalities, 47% female representation) * Direct access to leadership, flat structure, high transparency * Offices in **Belgium, Netherlands, Germany, Sweden, Portugal, and Romania** * A clear mission: make life easier for finance teams, HR, and employees across Europe